Stroke adjusting mechanism



Nov. 1, 1960 c. A. JOHNSON 2,958,237

STROKE ADJUSTING MECHANISM Filed Aug. 1, 1958 I 2 Sheets-Sheet 1 INVENTOR.

QAQEY A. IGHNSQN ATTDZNEVS Nov- 1 19 c. A. JOHNSON 2,958,237

STROKE ADJUSTING MECHANISM Filed Aug. 1, 1958 2 Sheets-Sheet 2 I 52 50 72 34 74 4 Z .ZE" \g 4= INVENTOR- CAREY A. JOHNSON ATTORN EYS United States Patent 2,958,237 STROKE ADJUSTING MECHANISM Carey A. Johnson, North Hancock St., McLeansboro, Ill.,

assignor, by direct and mesne assignments, of onesixth to Thomas L. Clark, Bluford, one-sixth to Kenneth E. Bush, Robinson, and one-third to Mabel L. Hefner, Mount Vernon, Ill. 1

Filed Aug. 1, 1958, Ser. No. 752,629

2 Claims. (Cl. 74522) This invention relates to improved stroke adjusting mechanism for oil well pumping units.

The primary object of the invention is to provide simpler, more practical, more easily installed, and more quickly and easily adjustable mechanism of this kind, which enables finer and more accurate stroke adjustments, and which can be operated by one man.

Another object of the invention is to provide mechanism of the character indicated above which is readily applicable to conventional and standard forms of oil well pumping units.

A further object of the invention is to provide mechanism of the character indicated above which is composed of a small number of simple and easily assembled and disassembled parts, and which can be made in rugged and serviceable forms at relatively low cost.

Other important objects and advantageous forms of the invention will be apparent from the following description and the accompanying drawings, wherein, for purposes of illustration only, a specific form of the invention is set forth in detail.

In the drawings:

Figure 1 is a side elevation of mechanism of the invention installed on an oil well pumping unit;

Figure 2 is an enlarged fragmentary and contracted perspective view of the walking beam of said unit and the mechanism mounted thereon;

Figure 3 is a further enlarged vertical longitudinal section taken on the line 33 of Figure 2; and

Figure 4 is a vertical transverse section taken on the line 4-4 of Figure 3.

Referring in detail to the drawings, wherein like numerals designate like parts throughout the several views, the numeral 10 generally designates a conventional or standard form of oil well pumping unit which comprises a base 12 upon which is mounted an upstanding Samson frame 14, having transversely spaced walking beam bearings 16 on its upper end, through which extends a pin 18 which extends through a beam saddle 20 fixed to the underside of a walking beam 22, as indicated at 24. The saddle 20 is located near to and is spaced from the cable head 26 on the forward end of the beam 22 and is located at a greater distance from the rear end 28 of the beam.

Mounted on the base 12 are cranks or eccentrics 30 driven by a motor 32, and vertical pitmans 34 are pivoted .at their lower ends to the eccentrics 30, as indicated at 36, and have upper ends 38 which are positioned at opposite sides of the beam 22 and are secured on pposite ends of a pin 40 which is journaled through a beam bearing 42.

In accordance with the present invention, the beam bearing 42 is a component of an adjustable assembly which is generally designated 44, and which comprises a slide consisting of a plate 46 which rests slidably upon the top or upper side 48 of the beam 22 at a location between the beam saddle 20 and the rear end 28 of the beam 22, the slide plate 46 having along its side edges longitudinal hook flanges 50 which slidably embrace the top side flanges 52 of the beam 22, whereby the slide is mounted on and is confined to endwise movements lengthwise of the beam 22. 7

As clearly shown in Figures 3 and 4, the beam bearing 42 rests upon the slide plate 46 near the rear end thereof and is secured in place, as by bolts 54 traversing the flanged base 56 of the bearing 42 and the slide plate 46, the bolts 54 having heads 58 which are countersunk flush with the underside of the plate 46.

The assembly 44 further comprises an upstanding preferably L-shaped bracket 60 fixed upon the slide plate 46 in front of the bearing 42, and involving a foot portion 62 secured to the plate 46, as by'countersunk bolts 64, and a standard portion 66 having therethrough a smooth bore or hole 68, which is lubricated by a grease fitting 70. i

Threaded upwardy through the horizontal components 72 of the hook flanges 50 on the slide plate 46 are longi: tudinally spaced set screws 74 which are arranged to lockingly engage the undersides of the top flanges 52 of the beam 22, so as to provide for locking the assembly 44 in selected longitudinally adjusted positions along the beam 22.

Adjusting and holding means for the slide assembly 44 comprises a relatively stationary upstanding block 76 fixedly mounted on the top of the beam 22, preferably at a location close to and to the rear of the saddle 20, and having therethrough a horizontal longitudinal bore 78 which is axially aligned with the bore 68 of the bracket 60. The flanged base 80 of the block 76 and the side flanges 52 of the beam 22 are traversed by securing bolts 82, which secure the block 76 removably in place.

Threaded through the bore 78 of the block 76 is an adjusting screw 84 having a rear end 86 which bears against the forward side of the standard 66 of the bracket 60 and has an extension thereof a smooth reduced diameter axial pintle 88 which is journaled through the bracket bore 68. Removably fixed on the pintle 88 and bearing against the rear side of the bracket Standard 66 is a collar 90, secured in place, as by a cotter pin 92, whereby endwise movements of the screw 84 in either direction adjusts the slide assembly 44 along the beam 22 substantially without lost motion.

For rotating the screw 84 to produce adjustments of the assembly 44 along the beam, while the set screws 74 are loosened, the forward end of the screw 84 is provided with an enlarged fluted head 94, on which is removably mounted a ratchet socket 96 having a lateral handle 98, and ratchet adjustment 100 which is adapted to be set so that swinging of the handle in opposite directions produces rotation of the screw 84 in the desired directions.

Adjustment of the slide assembly 44 forwardly, that is, toward the walking beam head 26, produced simply by loosening the set screws 74 and rotating the screw 84 by means of the ratchet handle 98, and then retightening the set screws 74 to hold the assembly 44 in a selected position along the beam 22, produces shortening of the vertical stroke of the beam head, while a similar adjusting operation, in which the assembly 44 is shifted rearwardly along the beam 22, produces lengthening of the vertical stroke of the beam head 26.

It is to be noted that the described adjustments do not involve undesirable shifting of the beam 22 relative to the Samson frame and arrangement misalignment of the head 26 with a well (not shown) being pumped; and that no equipment other than hand wrenches for loosening and tightening the set screws 74 is required, so that adjustments can be made easily and accurately in a short time by a single worker.

Although there has been shown and described herein a preferred form of the invention, it is to be understood that the invention is not necessarily confined thereto, and that any change or changes in the structure of and in the relative arrangements of components thereof are contemplated as being within the scope of the invention as defined by the claims appended hereto.

What is claimed is:

1. A pumping unit comprising a support, a solid walking beam having forward and rear ends, means rockably mounting the walking beam on the support at a point between and spaced from the ends of the beam, said beam having a top side and having lateral flanges at said top side, a slide slidably mounted on said top side and having hook flanges engaged over related lateral flanges of the beam, said slide being located to move along an intermediate part of the top side of the beam, a block fixed on said top side at a point spaced from said forward end of the beam and said slide, a screw threaded through said block, said screw having a rear end rotatably and securably connected to said slide, and means for rotating the screw.

2. A pumping unit comprising a support, a solid walking bearn having forward and rear ends and a top side,

means rockably mounting said beam on the support at a point intermediate the ends of the beam, a slide slidably and removably mounted upon said top side of the beam, means on said slide for pivoting a pitman to the slide, a block fixed on said top side-of the beam at a point between the forward end of the beam and said slide, an adjusting screw threaded through said block and having a rear end rotatably fixed to said slide, and means for rotating said screw, said block being located in the region'of said beam mountingimeans.

References Cited in the file of this patent UNITED STATES PATENTS 

